Police and federal agents scoured Northern California on Wednesday for a “violent psychopath” accused of murder who escaped a Hawaiian psychiatric hospital this week.

Randall Saito, 59, was acquitted of a gruesome 1979 murder by reason of insanity and committed to Hawaii State Hospital. Police said he escaped from the facility Sunday morning, hopped on a charter plane to Maui and then boarded a Hawaii Airlines flight to San Jose, Calif.

Honolulu police said Saito is considered extremely dangerous and should not be approached.

The FBI and U.S. Marshals Service have reviewed security footage from San Jose International Airport in connection with the manhunt, said Jon Vaden, an airport spokesman. He said police have not advised him of any threats at the facility.

Saito was committed to the hospital outside Honolulu in 1981, two years after he was acquitted in the killing of Sandra Yamashiro. Saito randomly chose the victim, shot her in the face and fatally stabbed her, authorities said. Her body was later found in her car at the mall.

A massive, multi-agency manhunt for a man described as a "psychopathic predator" is now focused in California after authorities discovered his well-planned escape from the Hawaii State Hospital included a cab ride, a chartered plane, thousands in cash, and a ticket to San Jose purchased online.

As the manhunt continues, new developments over Randall Saito's past emerge.

Documents from 1993 obtained by Hawaii News Now revealed that Saito had sexual relations with at least three hospital staff members. Saito has been known for his manipulative nature, and sources say sexual relations took place on multiple occasions where he was able to obtain contraband.

There were also growing questions Tuesday about why it took hours for State Hospital staff to report Randall Saito's escape on Sunday.

Saito had fled Oahu to Maui and then boarded a flight to California before law enforcement officials knew the "violent psychopath" was gone.

State Hospital officials declined to elaborate on the timeline surrounding Saito's escape, citing privacy issues and an ongoing investigation. But that didn't stop lawmakers from blasting state officials.

Meanwhile, the state attorney general said Tuesday night that Saito had been charged with felony escape. There's a $500,000 bench warrant for Saito's arrest.

“This is a dangerous individual. We need him off the streets," said state Attorney General Doug Chin. "The state is in close contact with law enforcement to make this happen.

Surveillance video in the cab clearly shows that when Saito got in he had a backpack stuffed with supplies, including a cell phone with a portable charger. He hadn't had that backpack when he escaped from the State Hospital.

During the ride, Saito is seen texting on the phone, then starts rifling through the backpack as if he's seeing what's inside for the first time.

Sources say that there are other facts that show Saito had planned his escape well in advance: His ticket to California was purchased online, and he paid for both his cab ride and his charter flight in cash, using an assumed name.

After being dropped off at the airport, Saito jumped on a charter plane to Maui, then boarded a Hawaiian Airlines flight for California.

That flight landed about 5:30 p.m. Sunday Hawaii time.

The state Health Department didn't report his escape to authorities until about 7:30 p.m., and authorities put out an alert to the community about 8:20 p.m.

It's not known whether Saito is still in California, though officials have said he has family there.

Federal agencies, including the FBI and U.S. Marshals, have joined the growing manhunt for him.

Authorities have called Saito a "violent psychopath," and prosecutors have argued for years that he should not be unsupervised in the community. He was acquitted by reason of insanity in 1979 of the gruesome murder of a woman at Ala Moana Center.